Display system using system level resources to calculate compensation parameters for a display module in a portable device

ABSTRACT

A system including a display module and a system module. The display module is integrated in a portable device with a display communicatively coupled to one or more of a driver unit, a measurement unit, a timing controller, a compensation sub-module, and a display memory unit. The system module is communicatively coupled to the display module and has one or more interface modules, one or more processing units, and one or more system memory units. At least one of the processing units and the system memory units is programmable to calculate new compensation parameters for the display module during an offline operation.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application No. 61/976,910, filed Apr. 8, 2014, entitled “Display System with Shared Level Resources for Portable Devices”.

BACKGROUND OF THE INVENTION

As discussed in previous documents and patents, IGNIS Maxlife™ implementations can compensate for both organic light emitting device (OLED) and backplane issues including aging, non-uniformity, temperature, and so on. Calculations of compensation factors are performed with dedicated resources of an electronic video display.

BRIEF SUMMARY

To bring MaxLife™ complexity to a comfort level of portable electronic device applications, measurement of an electronic video display panel (such as an organic light emitting or OLED display) is moved to an offline stage. Accordingly, such a timing controller (“TCON”), a measurement scheduler, a calculation module, a driver circuitry, and a memory interface become much simpler.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic illustrating integration of a MaxLife™ display into portable electronic devices, such as mobile devices (smartphones) or handheld tablet computers.

DETAILED DESCRIPTION

A system level simplification includes a plurality of possible modifications and simplifications, as described in the following table according to each module or block by way of example:

Example Functions TCON Only focused on either driving the OLED pixels or measurement of the pixel circuits at a time No correction is needed to eliminate the effect of measurement on driving and vice versa. Measurement Everything can happen sequentially and so Scheduler switching between different measurement methods is very simple. Calculation module System resources can be used to calculate part of (or all of) the new compensation value for each pixel circuit during offline modes. Driver Circuitry Drivers that drive each of the pixel circuits do not need to support different timing at the same time. Memory interface System memory can be used for calculations and so only storage memory will be needed.

While the electronic video display of the portable electronic device can have dedicated blocks for all the functions such as calculating the compensation values, and controlling the measurement scheduler, some of the above blocks can be shared with or offloaded to system level resources to simplify the overall integrated system. In reference to FIG. 1, a system configuration is illustrated in connection with electronic displays. According to the example of FIG. 1, a typical system of a portable electronic device includes multiple processing units such as generic processors, graphic processors, etc. Additionally, multiple memory blocks are used in a typical system. The data can be sent from the system through interface blocks to one or more electronic displays. There are two main sections in the system configuration shown in FIG. 1: a display module and a system block. The display module includes a substrate that carries the pixels used to display information from the portable electronic device. The system block is physically arranged on one or more substrates separate from the substrate carrying the display module. One or more connector cables can interface the display module with the system block to communicate information, power, and/or data therebetween.

The electronic display can include a compensation block, a timing controller, a memory unit, and a measurement unit that can be shared with other interface modules, such as an electronic touch screen. During offline operation of the portable electronic device (e.g., when the portable electronic device is in a standby mode), the system processing and memory units of the portable electronic device can be used to perform display or pixel measurements (e.g., measurements of individual or sets of pixel circuits in the OLED display of the portable electronic device) and to calculate new compensation parameters while the portable electronic device is in an offline operation (e.g., the display is dark or not emitting light). Additionally, at least one or more of the pixel measurements can be done during an inline operation (e.g., while pixels of the electronic video display are emitting light) of the portable electronic device, using system resources or display resources. The measurements and compensations can be carried out using any conventional technique previously described, such as in previous documents and patents assigned to Ignis Innovation Inc.

The interface between system block diagram and display memory for updating some of the parameters can be achieved through the main memory bus or through the display video interface. When the OLED display is in a compensation mode, the main video interface can be used to transfer the parameters to the display memory or to receive the measurement values from the display. Additionally, some of these interfaces can be shared with other blocks, such as an electronic touch screen commonly found on mobile devices and tablet computers.

To reduce the power consumption during calibration of the electronic display of the portable electronic device, only those resources required for calibration stay powered ON, with the reset going to power saving mode (where the applicable resources work at lower operating frequency or lower operating voltage) or shutting down completely. The terms measurement, driving, calibration, and compensation have the meanings as those of ordinary skill in the art of OLED display technology would understand and use those terms. They refer to different functions, each of which is well known to the OLED display designer.

In addition, the available resources, such as battery range, can be a factor to enable the display calibration. For example, if the battery charge is less than a threshold, the display calibration can be put on hold until the battery is charged or the battery of the portable electronic device is being charged. According to another example, a multi-tiered compensation system depends on available resources that include having a battery lower priority compensation (or calibration), which can be postponed. In other words, compensations can be carried out according to their assigned priority level and available battery charge (and, by implication, available resources).

The compensation or calibration or both can be prioritized based on one or more parameters, area, color, or last calibration time. For example, in reference to emissive displays, blue OLED sub-pixels age faster than other sub-pixels (such as red and green), and, as such, blue OLED sub-pixels can have a higher priority than other sub-pixels (which are assigned respective lower priorities).

According to another feature, priority can be assigned based on static images. For example, some areas of the portable electronic display can have static images most of the time (e.g., in a periphery area of the display panel, such as a top or bottom section). These areas can have higher priority for calibration (compensation) purposes. 

What is claimed is:
 1. A portable electronic device comprising: a driver unit; a timing controller; a display memory unit; an electronic video display communicatively coupled to at least one of the driver unit, a measurement unit, the timing controller, a compensation sub-module, and the display memory unit, each of which uses display resources, wherein the driver unit, the timing controller, the display memory unit, the electronic video display, are all included in a display module carried on a first substrate and integrated in the portable electronic device; one or more interface modules; one or more system memory units; at least one processing unit, included in a system module physically arranged on one or more substrates separate from the first substrate, and configured to execute system level applications of the portable electronic device and, during an offline operation in which the electronic video display is off, to perform calculations, offloaded from or shared with said compensation sub-module, for new compensation parameters for the display module, using system level resources distinct from the display level resources, including using the one or more system memory units; and a connector cable configured to interface the display module with the system module.
 2. The apparatus of claim 1, wherein the measurement unit carries out measurements of pixels of the electronic video display unit using the system level resources or the display resources or both during an inline operation while pixels of the electronic video display are emitting light.
 3. A method of operating a portable electronic device including, a driver unit, a timing controller, a display memory unit, an electronic video display communicatively coupled to at least one of the driver unit, a measurement unit, the timing controller, a compensation sub-module, and the display memory unit, each of which uses display resources, wherein the driver unit, the timing controller, the display memory unit, the electronic video display, are all included in a display module carried on a first substrate and integrated in the portable electronic device, one or more interface modules, one or more system memory units, at least one processing unit, included in a system module physically arranged on one or more substrates separate from the first substrate, a connector cable configured to interface the display module with the system module, the method comprising: executing at the at least one processing unit, system level applications of the portable electronic device; and during an offline operation in which the electronic video display is off, performing at the at least one processing unit, calculations, offloaded from or shared with said compensation sub-module, for new compensation parameters for the display module, using system level resources distinct from the display level resources, including using the one or more system memory units.
 4. The method of claim 3, further comprising: carrying out, at the measurement unit, measurements of pixels of the electronic video display unit using the system level resources or the display resources or both during an inline operation while pixels of the electronic video display are emitting light. 